1. Field of the Invention
This invention relates to a commercial cooking oven heated by gas to generate steam and hot air, and in particular to the means for generating the heat, generating the steam, supplying the fuel mixture, feeding of water for generating the steam, and exhausting the fumes and steam.
2. Prior Art
Patent EP-0 244 538 describes a cooking oven which incorporates an air turbine and a cylindrical water sprayer for generating steam coupled to the turbine shaft, fed by a line through a solenoid valve controlled by a cooking mode selector. This water sprayer is positioned inside the air turbine and throws off water droplets tangentially, and it is fed with cold water from the line.
The oven described in patent EP-0 277 888 incorporates a gas burner fed by an air/gas mixing device with a blower and one common duct for exhausting the fumes from combustion and the steam. The steam generator is independent, and it is separate from the burner, since it is powered by electricity. When the flame is extinguished, condensation is prevented from forming on the burner and the electrodes by a second air current through the burner feed duct. The second air current is heated by an auxiliary source.
In known gas ovens, the heater of the air that warms the food and the heater of the water that generates the steam are independent, and the full power of the gas burner is used to heat the air, being complemented by electric power to generate the steam. To keep steam from entering the gas burner and its feeding duct, and to keep moisture out of their control electrodes, known ovens use additional means unrelated to the burner.